Dripping Faucet? Stop the Drip Tonight
- 30 to 45 minutes
- 8 parts and tools
A dripping faucet is the kind of problem that seems small until it has kept you awake for three nights and added money to your water bill. The good news is that most drips come from one worn part inside the handle, usually a cartridge or a rubber washer, and replacing it is a straightforward job you can do tonight. Set aside 30 to 45 minutes, including a trip to the store if you do not already have the part. The most important step is the first one: shut off the water before you take anything apart. Everything after that is just unscrewing things in order and putting them back.
What's probably wrong
Work through these causes in order, because they are listed from most likely to least likely.
A worn cartridge is the number one cause on modern faucets. Most faucets made in the last 30 years use a cartridge, which is a small cylinder that controls water flow and temperature as you move the handle. Inside the cartridge are seals and moving parts that wear out over time, especially in hard water. When a seal fails, water sneaks past even with the handle fully off, and you get a steady drip from the spout. If your faucet has a single handle that controls both hot and cold, it almost certainly uses a cartridge.
Worn washers and O rings are the classic cause on older two handle faucets. A compression faucet, the kind where you turn the handle several rotations to shut it off, uses a rubber washer pressed against a valve seat. That washer hardens, cracks, and grooves over time until it cannot seal. O rings, which are small rubber rings around the cartridge or valve stem, also wear out and let water seep past. If your faucet drips from around the handle itself rather than from the spout, O rings are the prime suspect.
A corroded or damaged valve seat is less common. The valve seat is the metal rim the washer or cartridge seals against. Mineral scale and corrosion can pit that rim, so even a brand new washer cannot seal flat against it. This cause explains the faucet that keeps dripping after you replaced the washer. It is fixable, but it needs a special tool called a seat wrench, or a pro.
Loose or worn handle parts are the least dramatic cause. A handle that wobbles, or a retaining nut that has worked loose, can stop the cartridge from seating fully. This is easy to check and easy to fix, and it is worth ruling out before you buy parts. If the drip started right after someone leaned on the handle or a child swung on it, check the handle assembly first.
Fix it tonight
Start by shutting off the water. Look under the sink for two small valves on the water lines, one hot and one cold. Turn both clockwise until they stop. Then open the faucet to let any remaining water drain out and to confirm the shutoff worked. If the valves are seized or they drip when you turn them, stop and read the pro section, because a bad shutoff valve turns a small job into a wet one. If your faucet has no shutoff valves under the sink, you will need to shut off water to the house at the main valve, which is a bigger step but still fine for tonight.
First, plug the drain. Put the stopper in or lay a towel over the drain opening. Faucet screws are tiny, and they will find the drain if you give them the chance. Take a photo of the handle and the faucet from a couple of angles before you start. That photo is your map for reassembly.
Second, remove the handle. Look for a small set screw on the underside or back of the handle, often hidden under a decorative cap that pops off with a flathead screwdriver. Loosen the set screw and lift the handle off. On some faucets the handle unscrews directly, or a decorative dome cap unscrews by hand. Work gently. If a part resists, stop and check for a hidden screw rather than forcing it. Forcing a stuck handle can crack the finish or break the cartridge stem.
Third, remove the retaining nut and pull the cartridge or valve stem. Once the handle is off, you will see a nut holding the cartridge in place. Unscrew it with adjustable pliers, protecting the finish with a cloth between the pliers and the nut if you care about scratches. Note the exact orientation of the cartridge before you pull it out. Many cartridges have a notch or a tab that must go back in the same position, and putting it in backwards can reverse your hot and cold. Pull the cartridge straight out. If it resists, wiggle it gently side to side while pulling. Do not twist hard, because a stuck cartridge can break off inside the valve body.
Fourth, match the part. Take the old cartridge, washer, or O rings with you to the hardware store, or match them against the photos you took and the faucet brand name, which is often printed on the handle cap or the base. Cartridges are brand and model specific, so a close match is not good enough. If the store does not have your exact cartridge, a universal repair kit for your faucet brand is the next best option. While you are there, pick up plumber's grease, a small tube of silicone lubricant made for faucet parts. A thin coat on the new O rings helps them seal and last longer.
Fifth, install the new part and reassemble in reverse order. Grease the O rings lightly, slide the cartridge in with the same orientation as the old one, tighten the retaining nut snugly but not with all your strength, and put the handle back on. Tighten the set screw. Remove the drain plug, turn the shutoff valves back on slowly, counterclockwise, and watch the connections under the sink for drips while the faucet pressurizes. Then turn the faucet on and off a few times. Check the spout for dripping with the handle fully off. Wait a minute and check again, because a slow drip can take a moment to show up.
If the drip persists after a new cartridge, the valve seat is the likely problem. A seat wrench can resurface a pitted seat, but it is a fiddly tool and it is easy to make things worse if you have never used one. That is a reasonable place to stop for the night and call a pro in the morning. You have already ruled out the most common causes, and you can tell the plumber exactly what you replaced, which saves diagnostic time.
Parts and tools
When to call a pro
Call a plumber if the shutoff valves under the sink are seized, corroded, or leak when you turn them. Call a pro if the cartridge is stuck and will not come out with gentle wiggling, because forcing it can break it inside the valve body and turn a cartridge swap into a faucet replacement. Call a pro if a new cartridge did not stop the drip, which points to a damaged valve seat. Call a pro if you see water damage, mold, or soft wood under the sink, because the drip may have been going on longer than you think. Call a pro if your faucet is a wall mounted or specialty model you cannot identify, because parts matching matters and guessing wastes money.
What a pro typically costs
These are broad typical ranges, not quotes. Your area will change the number. A plumber visit to fix a dripping faucet typically costs 150 dollars to 350 dollars, including a replacement cartridge. Replacing a valve seat or resurfacing one typically costs 200 dollars to 400 dollars. Replacing the entire faucet, if the old one is too corroded or parts are unavailable, typically costs 300 dollars to 800 dollars installed, depending on the faucet you choose. A simple cartridge swap sits at the low end of these ranges. If a plumber quotes a full replacement for a drip that a cartridge would fix, ask them to explain why, and get a second opinion if the answer is vague.
FAQ
How do I find the right cartridge for my faucet?
Start with the brand name, which is usually on the handle cap, the base, or the spout. Then take the old cartridge to the store and match it by shape, length, and the position of its notches. Cartridges are brand and model specific. If you cannot find the brand, take clear photos of the faucet and the old cartridge to the store, and the staff can usually identify it.
My faucet drips from the handle, not the spout. Is that different?
Yes, and it usually means O rings rather than the cartridge seal. Water seeping around the base of the handle points to worn O rings on the cartridge or valve stem. The fix is the same process, but you may only need new O rings instead of a whole cartridge. Grease the new rings lightly before installing them.
Can I just tighten the handle harder to stop the drip?
No, and you can make it worse. Overtightening a modern faucet does not improve the seal, because the seal comes from the cartridge, not from handle pressure. On older compression faucets, cranking the handle harder just wears the washer faster. Replace the worn part instead.
How much water does a dripping faucet waste?
A faucet dripping once per second can waste several gallons a day, which adds up to hundreds of gallons over a month. A fast drip wastes far more. It is worth fixing tonight even though it seems minor, because the water bill and the wear on the fixture both grow with time.